1. Field of the Invention
This invention relates generally to the display of information on small display screens, and in particular to methods for displaying information having a width greater than the screen display width.
2. Description of Related Art
Next generation pocket size devices such as cellular telephones and pagers as well as desk-top telephones are now capable of receiving and displaying structured textual information which originated outside of the device. However, these devices usually have display screens with varying screen sizes and consequently varying screen display widths. Thus, the author of the structured textual information cannot customize the layout of the information for the screen size of a specific device because the screen size is device dependent.
In view of the variations in screen size among devices, prior art solutions for displaying structured information have attempted to dynamically adapt to the information being received and to display the information in a way which is best suited to making the information usable to the user. Ideally, the user would be able to see as many of the structure elements as possible at once, and would be able to see the complete text of any element when needed.
Currently, there are three alternative solutions to the problem of displaying text which exceeds the width of a small screen display such as those on cellular telephones, or pagers. As explained more completely below, none of the current display methods solves the problem of having the device dynamically adapt to the size of the elements being displayed. Further, the current methods make compromises with respect to allowing the user to see as many of the elements as possible at once, and to see the complete text of any element when needed.
In a first method, if the text of an element 110 is longer than screen display width 101, the text is wrapped and made to flow down the display screen as illustrated in FIG. 1A. In FIGS. 1A to 1D, the rectangle defined by the solid lines represents the display screen. The other elements in the structured textual information are shown simply to provide context for the following description.
In this method, the elements which do not fit on screen display 125, e.g., choices 111 to 113, are clipped and can be accessed by scrolling down vertically. This is similar to the method used by computer word processors for example. The fact that the text is structured into four elements 110 to 113 is not considered in displaying the text. Elements 110 to 113 are considered one continuous text message.
The vertical scrolling can be one line at a time, one screen display at a time (See the discussion of FIGS. 3A to 3D), or a faction of a screen display at a time. In this example, one line is scrolled at a time and so after a scroll, screen display 125 is as shown in FIG. 1B. The user sees a portion of element 110 and a portion of element 111.
As illustrated in FIGS. 1A to 1D, at any instant, the user is not able to view even a portion of all four of the choices in the list on screen display 125. In this embodiment, with a four line screen display, the user can view at most one complete choice. The user must scroll vertically to see the other choices. This makes it very hard for the user to remember what the choices are as the user has to remember prior choices while scrolling to see other choices.
A second display method has been to display a message with multiple lines as a single line and automatically scroll the multiple lines horizontally across the screen display. This is similar to the way one line of information is displayed for example on Times Square in New York.
The second method, where the text is fit on one line and scrolled horizontally, would not be applicable to our example. Scrolling the concatenated text of the four choices on one line, as illustrated in FIG. 2, would make the system unusable for the user.
A last display method used is a hybrid of the two methods described above. Text is wrapped on the screen display and after a short pause, long enough for the text to be read, the text automatically scrolls vertically, usually a full screen display at a time. This display method is illustrated in FIGS. 3A to 3D where each element is displayed individually in this example.
The last method has the same pitfalls as the first one by allowing the user to see only one choice at a time. The fact that the screen display scrolls automatically to the next screen display makes it harder for the user to remember the choices as the automatic scroll can occur before the user had time to understand the choices presented to him or her.
The three scrolling methods described above are well suited to the display of unstructured textual information such as a text message. They are often used in pagers or cellular telephones which support paging.
However, as illustrated above, the methods do not work well for structured elements, such as those in a list of user choices, a menu of user options, or a list of data that are presented on a display screen which is too small to display all of the structured elements in their entirety. In each of the methods, although structured information was considered, the method simply processed the structured information as one continuous string of text without regard to the elements within the structure.
Presenting a structured list on a small display screen presents many unresolved challenges. The reason this problem has not been solved is that up to now devices with a small display such as pagers or cellular telephones either displayed information which had been preprogrammed into the device, or displayed non-structured textual information.
In the case of information which had been preprogrammed into the device, such as a menu of choices pertaining to the configuration of the device, the engineers who programmed these menus made sure that the information had been optimized to the device and chose the wording to make sure that the choices fit within the width of the screen display.
When information originates outside of the device, only the case of non-structured information has been implemented and the methods described above are used with good results. When structured information originates outside of the device and is meant to be displayed on devices with various display screen sizes, there is no way to layout, i.e., preprogram, the information for a particular screen display size. Thus, a solution of the problems associated with displaying structured information on small display screens is needed before structured information, such as a menu of choices, can be advantageously used on telephones, cellular telephones, pagers and other devices with small display screens.